KR101137118B1 - Retardation film and polarizing plate and liquid crystal display comprising the same - Google Patents

Abstract

The present invention comprises an optically anisotropic polymer compound having a specific molecular weight in a retardation film containing a transparent polymer resin and an optically anisotropic polymer compound, and more specifically, an optically anisotropic polymer compound by extension processing. It relates to a retardation film, a polarizing plate containing the retardation film, and a liquid crystal display device.

Description

Retardation film, polarizing plate and liquid crystal display including the same {RETARDATION FILM AND POLARIZING PLATE AND LIQUID CRYSTAL DISPLAY COMPRISING THE SAME}

The present invention comprises an optically anisotropic polymer compound having a specific molecular weight in a retardation film containing a transparent polymer resin and an optically anisotropic polymer compound, and more specifically, an optically anisotropic polymer compound by extension processing. It relates to a retardation film, a polarizing plate containing the retardation film, and a liquid crystal display device.

The recent expansion of the display market demands an optical material that demands a clearer image and is not simply a transparent material but is given higher optical characteristics. In particular, liquid crystal displays (LCDs) used in notebooks and monitor TVs have poor viewing angle characteristics compared to CRTs and PDPs, and various studies have been made to solve them.

For example, there exists a method of using the extension film obtained by uniaxial or biaxial stretching process to transparent films, such as a polycarbonate, a cellulose resin, or cyclic olefin resin, as a retardation film as a method of improving a viewing angle characteristic.

When the polycarbonate is used, the phase difference due to stretching is relatively large, but since the elastic modulus of light is large, the phase difference tends to change depending on the stretching process conditions or the use environment, and phase difference staining is likely to occur.

On the other hand, in the case of cyclic olefin resin or cellulose acetate-based resin, the transparency of the film is very excellent, but the retardation of the phase difference due to the stretching process is small, and in order to obtain a large phase difference, a lot of stretching is necessary, and a lot of stretching causes phase difference staining. Can be.

Recently, Japanese Patent Laid-Open Publication No. 2004-035347 reported a case where a retardation film was prepared by introducing needle-shaped inorganic particles into a cyclic olefin film using a retardation film manufacturing method. However, in the case of inorganic fine particles, the solubility in solvents is low and the density is high. It is difficult to disperse | distribute evenly to a solvent, it is inferior to stability, and it is easy to aggregate, and there exists a possibility that it may impair transparency of a polymer film.

In addition, Japanese Laid-Open Patent Publication No. 2006-154760 expresses a retardation film by adding and stretching a low molecular organic compound in a transparent polymer film, but the anisotropy property of the used organic compound is low and the effect of retardation expression is limited by extension of the polymer film and desired phase difference Many stretches are required for expression.

In addition, compounds having high anisotropy generally have high crystallinity, low solubility in solvents, low compatibility in polymer films, and difficulty in preparing transparent films due to precipitation / phase separation after mixing and processing. There is no solution.

In order to solve this problem, the present invention includes a specific polymer compound having excellent compatibility with a transparent polymer resin and having high anisotropy in an optical transparent film including the transparent polymer resin, and the anisotropic polymer by extension processing. An object of the present invention is to provide a retardation film in which a compound is oriented to express retardation, and a polarizing plate and a liquid crystal display including the retardation film.

The present invention (a) a transparent polymer resin; And (b) an optically anisotropic polymer compound having a weight average molecular weight of 500 to 100,000.

Moreover, this invention provides the polarizing plate containing the retardation film of the said invention.

In addition, the present invention provides a liquid crystal display device comprising any one or both of (i) the retardation film of the present invention and (ii) the retardation film of the present invention.

When the retardation film is prepared using the optically anisotropic polymer compound and the transparent polymer resin having a specific molecular weight according to the present invention, the desired phase difference can be expressed even by adding a small amount of the anisotropic polymer compound and small extension processing of the film. Therefore, the occurrence of retardation unevenness is small and the manufacture of a uniform retardation film is possible.

The retardation film of the present invention comprises (a) a transparent polymer resin and (b) an optically anisotropic polymer compound having a weight average molecular weight of 500 to 100,000, and preferably the optically anisotropic polymer compound is used for extension (stretching) processing. It is a retardation film oriented by. At this time, the weight average molecular weight of the (b) optically anisotropic high molecular compound is measured by GPC using polystyrene as a reference solution.

It is preferable that the retardation film of this invention is 10-500 nm in phase difference Re in a film plane, and 10-500 nm of phase difference Rth in a thickness direction.

In addition, it is preferable that the retardation film of the present invention is manufactured by extension processing, and due to the orientation of the (b) optically anisotropic polymer compound, the retardation film can be sufficiently expressed without much extension, thereby producing a retardation film having excellent transparency. It is possible.

In the present invention, the (a) transparent polymer resin is not particularly limited as long as it is a polymer resin having excellent transparency and can produce a film alone. For example, the polymer resin may be an alicyclic structure-containing polymer resin, a polycarbonate resin, a polyester resin, a polysulfone resin, a polyether sulfone resin, a polyether ketone resin, a polystyrene resin, a chain polyolefin resin. , Polyvinyl alcohol resin, polyvinyl chloride resin, polyacrylate resin, polymethacrylate resin, polyimide resin, polyamide resin, polyketone sulfide resin, polyarylene sulfide resin, poly It may be one or more selected from the group consisting of arylene ether resins, polyacetal resins and cellulose resins, but is not limited thereto. Among these, alicyclic structure-containing polymer resins, cellulose resins, polyacrylate resins and the like which are excellent in optical characteristics are particularly preferable.

The alicyclic structure-containing polymer resin has an alicyclic structure in the repeating unit of the polymer resin. Examples of the alicyclic structure-containing polymer resin include, but are not limited to, norbornene-based polymers, monocyclic cyclic olefin polymers, cyclic conjugated diene-based polymers, vinyl alicyclic hydrocarbon polymers, and hydrides thereof. Preferably norbornene-based polymers can be used.

Examples of the norbornene-based polymer include a ring-opening polymer of a norbornene-based monomer, a ring-opening copolymer of another monomer capable of ring-opening copolymerization with a norbornene-based monomer, and an addition polymer of those hydrides and norbornene-based monomers, and copolymerizable with a norbornene-based monomer. Addition copolymers with other monomers, and the like, but are not limited thereto. In addition, the norbornene-based monomers, other monomers that can be ring-opened copolymerized with the norbornene-based monomers, and other monomers that can be additionally copolymerized with the norbornene monomers are not particularly limited and may be known ones commonly used.

In addition, the cellulose resin is preferably a lower fatty acid ester of cellulose. In the lower fatty acid ester of cellulose, lower fatty acid means fatty acids having 6 or less carbon atoms, and examples thereof include, but are not limited to, cellulose acetate, cellulose propionate, cellulose butyrate, and the like.

In the present invention, the optically anisotropic polymer compound (b) having a weight average molecular weight of 500 to 100,000 is difficult to produce an original film, but is excellent in compatibility with a transparent polymer resin and can provide a high phase difference. It is not specifically limited.

In addition, the optically anisotropic polymer compound having a weight average molecular weight of 500 to 100,000 is not limited to a specific structure, and has an anisotropy and a polymer compound having a weight average molecular weight of 500 to 100,000, preferably a weight average molecular weight High molecular compounds of 1,000 to 30,000 can be used. If the weight average molecular weight is less than 500, there is a limitation in implementing anisotropy, and if the weight average molecular weight is more than 100,000, compatibility with the polymer resin is poor, which makes it difficult to prepare a transparent film.

The optically anisotropic polymer compound (b) may be an optically anisotropic polymer compound including a structure represented by the following Chemical Formula 1.

[Formula 1]

In formula ^1, R 1 is -H, -CN, an alkynyl group of _{-CO 2 H, -OH, -NH 2} , C 1 ~ C 30 alkyl group, C ₂ ~ C ₃₀ alkenyl group, C ₂ ~ C ₃₀ of the , Phenyl group, C ₆ ~ C ₃₀ aryl group, C ₁ ~ C ₃₀ alkyl ketone group, C ₆ ~ C ₃₀ aryl ketone group, C ₁ ~ C ₃₀ alkyl ester group, C ₆ ~ C ₃₀ aryl ester Group or halogen group;

R ² is —O—, —NH—, —O (CH ₂ ) _n O—, —NH (CH ₂ ) _n NH—, —O (CH ₂ ) _n NH—, —NH (CH ₂ ) _n O— , -C (= O) O-, -OC (= O)-, -C (= O)-, -C (= O) NH-, -NHC (= O)-, alkyl of C ₁ -C ₃₀ group, a C ₂ ~ C ₃₀ alkenylene group, C ₂ ~ C ₃₀ alkynylene group, a phenylene group, or aryl group of C ₆ ~ C _30, the n is an integer from 0 to 12.

At this time, the optically anisotropic polymer compound including the structure represented by the formula (1) can be produced by homopolymerization or copolymerization of a monomer having a structure represented by the formula (1) and a polymerizable functional group in accordance with a conventional method. In addition, the polymerizable functional group includes, but is not limited to, acrylic group, methacryl group, vinyl group, epoxy group, etc .; The monomer usable in the copolymerization is not particularly limited as long as it has a polymerizable functional group, and non-limiting examples include acrylate, methacrylate and the like.

The optically anisotropic polymer compound (b) is preferably an optically anisotropic polymer compound including a structure represented by the following formula (2).

[Formula 2]

In formula 2, R ³ is an alkynyl group of _{-H, -CN, -CO 2 H,} -OH, -NH 2, C 1 ~ C 30 alkyl group, C ₂ ~ C ₃₀ alkenyl group, C ₂ ~ C ₃₀ of the , Phenyl group, C ₆ ~ C ₃₀ aryl group, C ₁ ~ C ₃₀ alkyl ketone group, C ₆ ~ C ₃₀ aryl ketone group, C ₁ ~ C ₃₀ alkyl ester group, C ₆ ~ C ₃₀ aryl ester Group or halogen group;

R ⁴ and R ⁵ are each independently —O—, —NH—, —O (CH ₂ ) _n O—, —NH (CH ₂ ) _n NH—, —O (CH ₂ ) _n NH—, —NH ( CH ₂ ) _n O-, -C (= O) O-, -OC (= O)-, -C (= O)-, -C (= O) NH-, -NHC (= O)-, C ₁ - and C ₃₀ alkylene group, arylene group, a C ₂ ~ C ₃₀ alkenylene group, C ₂ ~ C ₃₀ alkynylene group, phenylene group, or C ₆ ~ C ₁₂ of, n is an integer from 0 to 12 .

In this case, the optically anisotropic polymer compound including the structure represented by Formula 2 may be prepared by homopolymerization or copolymerization of a monomer having a structure represented by Formula 2 together with a polymerizable functional group according to a conventional method. In addition, the polymerizable functional group includes, but is not limited to, acrylic group, methacryl group, vinyl group, epoxy group, etc .; The monomer usable in the copolymerization is not particularly limited as long as it has a polymerizable functional group, and non-limiting examples include acrylate, methacrylate and the like.

Preferably, the monomer having both the structure represented by the formula (2) and the polymerizable functional group is preferably a compound represented by the following formula (3).

(3)

In formula (3), R ³ , R ⁴ and R ⁵ are as defined in formula (2).

On the other hand, in the retardation film of the present invention, (b) the optically anisotropic polymer compound may include one kind or two or more kinds. In the retardation film of the present invention, the weight ratio of the (a) transparent polymer resin: (b) the optically anisotropic polymer compound is 80: 20 to 99.9: 0.1, preferably 85: 15 to 99.5: 0.5 days. Can be.

The method for producing the retardation film according to the present invention is not particularly limited and may be in accordance with conventional methods known in the art.

As a non-limiting example, the retardation film of the present invention, after forming a transparent film from the mixture containing the (a) transparent polymer resin and (b) optically anisotropic polymer compound, the film is extended to the (b) optical It can manufacture by orienting an anisotropic high molecular compound. The birefringence of the retardation film can be easily controlled by adjusting the addition amount of the optically anisotropic polymer compound and the extension ratio of the film.

Further, in the production of the retardation film according to the present invention, the mixture containing the (a) transparent polymer resin and (b) the optically anisotropic polymer compound may include an organic solvent as necessary in addition to these. The use of the mixture may be facilitated by the inclusion of an organic solvent.

The organic solvent is not particularly limited, and conventional organic solvents known in the art may be used. Non-limiting examples thereof include hydrocarbons such as cyclohexane, cyclopentane, benzene, toluene, xylene and butylbenzene; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, and gamma-butyrolactone; Amides such as 2-pyrrolidone, N-methyl-2-pyrrolidone, dimethylformamide and dimethylacetamide; Halogens such as chloroform, dichloromethane, carbon tetrachloride, dichloroethane, tetrachloroethane, tetrachloroethylene and chlorobenzene; alcohols such as t-butyl alcohol, diacetone alcohol, glycerin, monoacetin, ethylene glycol, triethylene glycol, hexylene glycol, and ethylene glycol monomethyl ether; Phenols such as phenol and parachlorophenol; Methoxybenzene, 1,2-dimethoxybenzene, diethylene glycol dimethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, di Ethers such as ethylene glycol diethyl ether, dipropylene glycol dimethyl ether and dipropylene glycol diethyl ether. In addition, these organic solvents can be used individually or in mixture of 2 or more types.

In the production of the retardation film according to the present invention, the solid content of the (a) transparent polymer resin and (b) the optically anisotropic polymer compound is usually 1 to 70% by weight, preferably 2 to 1%, based on the total mixture containing the solvent. It is 50 weight%, More preferably, it is 3-50 weight%. If the concentration of the solids relative to the total mixture is less than 1% by weight, it is difficult to secure the thickness of the film. When the concentration of the solids is greater than 70% by weight, the viscosity of the entire mixture is so large that it is difficult to obtain a film of uniform thickness.

In addition, in the production of the retardation film according to the present invention, a method of forming a transparent film using a mixture containing the (a) transparent polymer resin and (b) optically anisotropic polymer compound is not particularly limited and is known in the art It is possible to follow known conventional methods. Non-limiting examples can be prepared by solvent casting or extrusion molding.

In the case of producing a transparent film by the solvent casting method, the mixture is applied on a support such as a metal drum, still belt, polyester film, Teflon, or glass, and the solvent is dried in a drying furnace using a roller and then removed from the support. It can manufacture by peeling a film. The amount of residual solvent in a transparent film is 10 weight% or less normally, Preferably it is 5 weight% or less, More preferably, it is 1 weight% or less. When the amount of residual solvent exceeds the above upper limit, the heat resistance of the film tends to be low.

As described above, the transparent film formed from the mixture containing the (a) transparent polymer resin and (b) the optically anisotropic polymer compound may be extended. By extension of the film, molecules of the transparent polymer resin are oriented, and along with the orientation of the polymer resin, the anisotropic polymer compound is arranged parallel to the film plane, and the degree of alignment may be adjusted according to the extent of extension.

At this time, the phase difference imparting performance can be controlled by the kind, content and extension ratio of the (b) the optically anisotropic polymer compound. That is, when the thickness of the film before extension is constant, the absolute value of the retardation tends to increase depending on the degree of the large number of the anisotropic compounds or the film having the large extension magnification. The retardation film which has can be obtained.

In the present invention, the (b) optically anisotropic polymer compound is capable of providing a sufficiently large phase difference even with a small amount of addition due to the large anisotropy, and since the desired phase difference can be expressed even with a small extension, there is less occurrence of phase difference staining. Production of a uniform retardation film is easy.

The optical retardation film of the present invention may include other additives for improving processability and physical properties of the film. Although the kind of additive is not specifically limited, Generally, the additive used for manufacture of an optical film is possible. Non-limiting examples thereof include stress relaxers, leveling agents, UV inhibitors, antioxidants, peeling accelerators, fine particles, infrared absorbers, and the like, which may be used alone or in combination of two or more thereof.

On the other hand, the polarizing plate of the present invention is characterized by including the retardation film according to the present invention, the liquid crystal display device of the present invention is also characterized by including the retardation film according to the present invention and / or the polarizing plate according to the present invention.

Other components and manufacturing methods of the polarizing plate and the liquid crystal display are well known in the art, and thus, description thereof will be omitted since the present invention may be sufficiently reproduced without a separate description.

Hereinafter, the present invention will be described in detail with reference to the following Examples. However, the following examples are merely to illustrate the present invention and the present invention is not limited by the following examples.

Synthesis Example 1

1.0 equivalent of Compound 1 was dissolved in a mixed solvent of ethanol: water = 7: 3 (v: v), and then 1.2 equivalent of 2-bromoethanol and 2.7 equivalent of KOH were added and stirred at 85 ° C. for 18 hours. The ethanol was distilled off under reduced pressure and completely removed, followed by additional water. 10% HCl (aq) was added slowly to adjust the pH between 1 and 3 to precipitate a solid, which was filtered to obtain Compound 2 in a yield of 80% or more. After 2.0 equivalents of Compound 2 was dissolved in DMAc solvent, 1.2 equivalents of acryloxy chloride was added at 0 ° C. and stirred at room temperature for 1 hour. After the completion of the reaction, work-up with ether and recrystallized with a small amount of ether to give the compound 3 in a yield of 90% or more. Compound 3 and 1.0 equivalent of 4-Cyano-biphenol were dissolved in CH ₂ Cl ₂ . 1.3 equivalent of EDC and 0.1 equivalent of DMAP were added thereto, followed by stirring at room temperature for about 18 hours. After completion of the reaction, the mixture was worked up with CH ₂ Cl ₂ , purified using silica gel, and recrystallized with methanol to obtain compound 4 (liquid crystal monomer) in a yield of 90% or more. This 0.65 equivalent of Liquid Crystal Monomer Compound 4 and 0.35 equivalent of Stearyl acrylate were dissolved in THF. A small amount of AIBN was added thereto and stirred for 4 hours. Methanol was added after completion | finish of reaction, and the precipitated solid was filtered and the final compound 5 (weight average molecular weight 3500) which is a liquid crystal polymer was obtained.

Synthesis Example 2

0.65 equivalents of the following compound 6 and 0.35 equivalents of Stearyl acrylate were dissolved in THF. A small amount of AIBN was added thereto and stirred for 4 hours. After completion | finish of reaction, methanol was added and the precipitated solid was filtered and the following compound 7 (weight average molecular weight 3500) which is a liquid crystal polymer was obtained.

Synthesis Example 3

Compound 9 (weight average molecular weight 3300) was obtained by polymerization in the same manner as in Synthesis Example 2, except that Compound 8 was used instead of Compound 6 as a monomer and Stearyl acrylate was not used.

(Example 1)

100 parts by weight of polymethyl methacrylate (PMMA) and 1.0 part by weight of the polymeric anisotropic compound 5 prepared in Synthesis Example 1 were dissolved in 400 parts by weight of methylene chloride, and then a film was prepared on a glass plate by casting. The residual solvent was removed by drying at 110 ° C. for 1 hour. The film was removed from the glass plate, cut into appropriate sizes, and stretched 1.5 times at 100 ° C. The film after stretching was a transparent film with uniform thickness and no retardation unevenness.

(Example 2)

A retardation film was manufactured in the same manner as in Example 1, except that 0.5 parts by weight of the polymer anisotropic compound 7 prepared in Synthesis Example 2 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Example 3)

A retardation film was manufactured in the same manner as in Example 1, except that 1.5 parts by weight of the polymer anisotropic compound 7 prepared in Synthesis Example 2 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Example 4)

A retardation film was manufactured in the same manner as in Example 1, except that 3.0 parts by weight of the polymer anisotropic compound 7 prepared in Synthesis Example 2 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Example 5)

A retardation film was manufactured in the same manner as in Example 1, except that 1.0 part by weight of the polymer anisotropic compound 9 prepared in Synthesis Example 3 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Comparative Example 1)

A retardation film was manufactured in the same manner as in Example 1, except that the anisotropic compound 5 prepared in Synthesis Example 1 was not used. The film was a transparent film with a uniform thickness and no retardation stain.

(Comparative Example 2)

A retardation film was manufactured in the same manner as in Example 1, except that 1.0 part by weight of the anisotropic compound 4 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Comparative Example 3)

A retardation film was manufactured in the same manner as in Example 1, except that 3.0 parts by weight of the anisotropic compound 6 were used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Comparative Example 4)

A retardation film was manufactured in the same manner as in Example 1, except that 1.0 part by weight of the anisotropic compound 8 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. The film was a transparent film with a uniform thickness and no retardation stain.

(Comparative Example 5)

A retardation film was manufactured in the same manner as in Example 1, except that 10.0 parts by weight of the anisotropic compound 4 was used instead of 1.0 part by weight of the polymer anisotropic compound 5 in Example 1. Although the film was uniform in thickness, retardation spots occurred and haze increased, resulting in poor transparency of the film.

(Characteristic Evaluation of Film)

The films obtained in Examples 1 to 5 and Comparative Examples 1 and 5 were measured for haze by a haze meter, and the phase difference of the film was measured with an axoscan of Axometrics. The measurement results are shown in Table 1 below.

The in-plane retardation Re and the retardation Rth in the thickness direction of the film are defined by the following equation. N _x and n _y are in-plane refractive indices, n _z is a refractive index in the thickness direction, and d is 70 μm as the thickness of the film.

Re = (n _x- n _y ) xd

Rth = ((n _x + n _y ) / 2-n _z ) xd

Haze Re Rth Example 1 0.2 101 57 Example 2 0.2 40 21 Example 3 0.2 105 61 Example 4 0.2 157 80 Example 5 0.2 89 46 Comparative Example 1 0.2 8 -4 Comparative Example 2 0.2 15 7 Comparative Example 3 0.2 30 14 Comparative Example 4 0.2 13 7 Comparative Example 5 1.5 95 49

As shown in the above results, in the case of containing an anisotropic polymer compound having a specific molecular weight distribution according to the present invention and expressing the phase difference by extension of the polymer resin, it does not contain an anisotropic polymer compound or a low molecular weight anisotropic compound It can be seen that a large phase difference expression is possible with a very small stretching than when the phase difference is expressed with the resin included.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, and that various changes and modifications may be made without departing from the scope of the invention. It is natural to belong.

Claims (13)

(a) a transparent polymer resin; And (b) a weight average molecular weight containing 500 to 100,000 optically anisotropic high molecular compound, Retardation film characterized in that the optically anisotropic polymer compound is an optically anisotropic polymer compound comprising a structure represented by any one of the following formulas 1 to: [Formula 1]

[Formula 2]

(3)

In Chemical Formulas 1 to 3, R ¹ and R ³ is an alkynyl group of _{-H, -CN, -CO 2 H,} -OH, -NH 2, C 1 ~ C 30 alkyl group, C ₂ ~ C ₃₀ alkenyl group, C ₂ ~ C ₃₀ of, Phenyl group, C ₆ ~ C ₃₀ aryl group, C ₁ ~ C ₃₀ alkyl ketone group, C ₆ ~ C ₃₀ aryl ketone group, C ₁ ~ C ₃₀ alkyl ester group, C ₆ ~ C ₃₀ aryl ester group Or a halogen group; R ² , R ⁴ and R ⁵ are each independently —O—, —NH—, —O (CH ₂ ) _n O—, —NH (CH ₂ ) _n NH—, —O (CH ₂ ) _n NH—, -NH (CH ₂ ) _n O-, -C (= O) O-, -OC (= O)-, -C (= O)-, -C (= O) NH-, -NHC (= O) -A C ₁ -C ₃₀ alkylene group, a C ₂ -C ₃₀ alkenylene group, a C ₂ -C ₃₀ alkynylene group, a phenylene group, or a C ₆ -C ₃₀ arylene group; n is an integer of 0-12. The method of claim 1, wherein the (a) transparent polymer resin is alicyclic structure-containing polymer resin, polycarbonate resin, polyester resin, polysulfone resin, polyether sulfone resin, polyether ketone resin, polystyrene Resin, linear polyolefin resin, polyvinyl alcohol resin, polyvinyl chloride resin, polyacrylate resin, polymethacrylate resin, polyimide resin, polyamide resin, polyketone sulfide resin, polyaryl A retardation film characterized in that it is at least one member selected from the group consisting of rensulfide resin, polyarylene ether resin, polyacetal resin, and cellulose resin. delete The optically anisotropic polymer compound including the structure represented by Chemical Formula 1 is prepared by homopolymerizing or copolymerizing a monomer having both the structure represented by Chemical Formula 1 and a polymerizable functional group. film. delete The method of claim 1, wherein the optically anisotropic polymer compound comprising a structure represented by the formula (2), characterized in that the phase difference is produced by homopolymerizing or copolymerizing a monomer having a structure represented by the formula (2) and a polymerizable functional group film. delete The retardation film according to claim 1, wherein the retardation film has a retardation (Re) in the film plane of 10 to 500 nm and a retardation (Rth) in the thickness direction of 10 to 500 nm. The retardation film according to claim 1, wherein the weight ratio of the (a) transparent polymer resin: (b) the optically anisotropic polymer compound is 80: 20 to 99.9: 0.1. The method according to claim 1, wherein after forming the film with a mixture containing (a) the transparent polymer resin and (b) the optically anisotropic polymer compound, the film is extended to orient the (b) optically anisotropic polymer compound. Retardation film characterized by. The retardation film of claim 1, further comprising at least one additive selected from the group consisting of a stress relaxer, a leveling agent, a UV inhibitor, an antioxidant, a peeling promoter, a particulate, and an infrared absorber. The polarizing plate containing the retardation film of any one of Claims 1, 2, 4, 6, and 8-11. (i) the retardation film of any one of claims 1, 2, 4, 6, and 8-11 and (ii) 1, 2, 4, and A liquid crystal display device comprising any one or both of the polarizing plate including the phase difference film of any one of claims 6 and 8.